The Belwin String Builder is a string class method in which the violin, viola, cello, and bass play together throughout. Each book, however, is a complete unit and may be used separately for class or individual instruction. The material in this book is realistically graded so that only a minimum of explanatory material is required. Each melody is interesting and will provide the basis for a fine left hand technic and bow arm. Available in three levels for violin, viola, cello, bass, piano accompaniment, and teacher's manual.Samuel Applebaum is the author of 'String Builder Violin Book One (Belwin Course for Strings)', published 1985 under ISBN 9780769251424 and ISBN 0769251420.